Zimmermann took a perfect game into the sixth inning and finished with a two-hitter and a career-high 12 strikeouts to lead the Washington Nationals to a 6-0 victory against the San Diego Padres on Sunday.

His game plan worked perfectly for spacious Petco Park.

"I was throwing strikes and the guys got me some runs early," he said. "My mentality changed to pour strikes into the zone and fill it up. Big ballpark, just let them hit the ball and I had a lot of strikeouts today which means my fastball was pretty good and I was able to locate it pretty good."

Zimmermann (5-2) faced only two batters over the minimum as he walked none in his first complete game of the season and sixth of his career. It was his third career shutout. His previous career high was 11 strikeouts, which he'd done twice.

The Padres were shut out for the 10th time, tops in the majors, and for the second time in the three-game series. Tanner Roark and the Nationals beat the Padres 6-0 Friday night in a combined three-hitter.

Zimmermann said he had a "pretty terrible" bullpen session before the game. "But I guess that's the way it works. When that's bad it's usually a game, but when you have a good bullpen you have a good game."

He said he didn't think about a no-hitter.

"That's really tough to do. My career numbers say I give up a hit an inning, so I figured they were going to get a hit at some point in the game. It was fun putting up the zeroes but the main thing was to go deep and win the ballgame."

San Diego's offensive ineptness was glaring against Zimmermann. He retired the first 16 batters before Alexi Amarista singled to right field. Zimmermann then struck out pinch-hitter Tommy Medica and Everth Cabrera to end the inning.

"From the first pitch, he was in the strike zone again," manager Matt Williams said. "Strike one is important. He was able to do that today. Fastball command -- he was throwing it exactly where he wanted to throw it."

"We just didn't see the ball," Padres manager Bud Black said. "We didn't pick it up off him. He pumped some fastballs on us early and mixed some breaking balls early on and we couldn't solve him."

The Padres entered the game with the lowest batting average in the majors, .220. In the span of seven games, they were two-hit twice -- also by Chris Sale of the Chicago White Sox -- and one-hit once, although they beat Pittsburgh in that game.

"Even with that lead, he hit his spots," Cameron Maybin said of Zimmermann. "He doesn't walk very many people. Sometimes you have to tip your hat. Guys like that are tough to come back against. The guy is pretty good.

"In our ballpark, if you can stay out of the middle of the plate, it's always tough, especially with his stuff," Maybin said. "He did a great job of locating his pitches today."

In his previous start, Zimmermann gave up five hits in eight shutout innings in a 7-0 win against Philadelphia.

San Diego's Seth Smith tripled leading off the eighth and was stranded.

Padres left-hander Eric Stults (2-7) lasted only 2 1/3 innings, the shortest of his 85 career starts. He allowed six runs and eight hits, struck out two and walked none.

Desmond hit a two-run homer to center field in the second inning to give the Nationals a 3-0 lead. It was his 13th. He also hit a two-run homer Saturday night to give the Nationals the lead in a game they would lose 4-3 in 11 innings.

Stults allowed three straight singles opening the third, including Adam LaRoche's RBI base hit. After getting Ryan Zimmerman to line out to first, Stults allowed a single to Desmond to load the bases and was pulled. Tim Stauffer came on and allowed Espinosa's two-run single.

Game notes
Nationals 3B Anthony Rendon missed his second straight start after getting hit in the hand by a smash by Carlos Quentin on Friday night. Williams said Rendon should be able to play Monday. ... The Nationals open a four-game series at San Francisco on Monday night, when RHP Stephen Strasburg (5-4, 3.10) is scheduled to start against RHP Ryan Vogelsong (4-2, 3.39). ... It'll be a homecoming for Williams, who played his first 10 big league seasons with the Giants. ... The Padres are off Monday before opening a three-game series Tuesday at Philadelphia.